<?
/**
* @author Jonatan Villela
* @copyright 2010
*/

class JUserHelper
{
/**
* Method to activate a user
*
* @param string $activation Activation string
* @return boolean True on success
* @since 1.5
*/
function activateUser($activation)
{
//Initialize some variables
$db = & JFactory::getDBO();

// Lets get the id of the user we want to activate
$query = 'SELECT id'
. ' FROM #__users'
. ' WHERE activation = '.$db->Quote($activation)
. ' AND block = 1'
. ' AND lastvisitDate = '.$db->Quote('0000-00-00 00:00:00');
;
$db->setQuery( $query );
$id = intval( $db->loadResult() );

// Is it a valid user to activate?
if ($id)
{
$user =& JUser::getInstance( (int) $id );

$user->set('block', '0');
$user->set('activation', '');

// Time to take care of business.... store the user.
if (!$user->save())
{
JError::raiseWarning( "SOME_ERROR_CODE", $user->getError() );
return false;
}
}
else
{
JError::raiseWarning( "SOME_ERROR_CODE", JText::_('UNABLE TO FIND A USER WITH GIVEN ACTIVATION STRING') );
return false;
}

return true;
}

/**
* Returns userid if a user exists
*
* @param string The username to search on
* @return int The user id or 0 if not found
*/
function getUserId($username)
{
// Initialize some variables
$db = & JFactory::getDBO();

$query = 'SELECT id FROM #__users WHERE username = ' . $db->Quote( $username );
$db->setQuery($query, 0, 1);
return $db->loadResult();
}

/**
* Formats a password using the current encryption.
*
* @access public
* @param string $plaintext The plaintext password to encrypt.
* @param string $salt The salt to use to encrypt the password. []
* If not present, a new salt will be
* generated.
* @param string $encryption The kind of pasword encryption to use.
* Defaults to md5-hex.
* @param boolean $show_encrypt Some password systems prepend the kind of
* encryption to the crypted password ({SHA},
* etc). Defaults to false.
*
* @return string The encrypted password.
*/
function getCryptedPassword($plaintext, $salt = '', $encryption = 'md5-hex', $show_encrypt = false)
{
// Get the salt to use.
$salt = JUserHelper::getSalt($encryption, $salt, $plaintext);

// Encrypt the password.
switch ($encryption)
{
case 'plain' :
return $plaintext;

case 'sha' :
$encrypted = base64_encode(mhash(MHASH_SHA1, $plaintext));
return ($show_encrypt) ? '{SHA}'.$encrypted : $encrypted;

case 'crypt' :
case 'crypt-des' :
case 'crypt-md5' :
case 'crypt-blowfish' :
return ($show_encrypt ? '{crypt}' : '').crypt($plaintext, $salt);

case 'md5-base64' :
$encrypted = base64_encode(mhash(MHASH_MD5, $plaintext));
return ($show_encrypt) ? '{MD5}'.$encrypted : $encrypted;

case 'ssha' :
$encrypted = base64_encode(mhash(MHASH_SHA1, $plaintext.$salt).$salt);
return ($show_encrypt) ? '{SSHA}'.$encrypted : $encrypted;

case 'smd5' :
$encrypted = base64_encode(mhash(MHASH_MD5, $plaintext.$salt).$salt);
return ($show_encrypt) ? '{SMD5}'.$encrypted : $encrypted;

case 'aprmd5' :
$length = strlen($plaintext);
$context = $plaintext.'$apr1$'.$salt;
$binary = JUserHelper::_bin(md5($plaintext.$salt.$plaintext));

for ($i = $length; $i > 0; $i -= 16) {
$context .= substr($binary, 0, ($i > 16 ? 16 : $i));
}
for ($i = $length; $i > 0; $i >>= 1) {
$context .= ($i & 1) ? chr(0) : $plaintext[0];
}

$binary = JUserHelper::_bin(md5($context));

for ($i = 0; $i < 1000; $i ++) {
$new = ($i & 1) ? $plaintext : substr($binary, 0, 16);
if ($i % 3) {
$new .= $salt;
}
if ($i % 7) {
$new .= $plaintext;
}
$new .= ($i & 1) ? substr($binary, 0, 16) : $plaintext;
$binary = JUserHelper::_bin(md5($new));
}

$p = array ();
for ($i = 0; $i < 5; $i ++) {
$k = $i +6;
$j = $i +12;
if ($j == 16) {
$j = 5;
}
$p[] = JUserHelper::_toAPRMD5((ord($binary[$i]) << 16) | (ord($binary[$k]) << 8) | (ord($binary[$j])), 5);
}

return '$apr1$'.$salt.'$'.implode('', $p).JUserHelper::_toAPRMD5(ord($binary[11]), 3);

case 'md5-hex' :
default :
$encrypted = ($salt) ? md5($plaintext.$salt) : md5($plaintext);
return ($show_encrypt) ? '{MD5}'.$encrypted : $encrypted;
}
}

/**
* Returns a salt for the appropriate kind of password encryption.
* Optionally takes a seed and a plaintext password, to extract the seed
* of an existing password, or for encryption types that use the plaintext
* in the generation of the salt.
*
* @access public
* @param string $encryption The kind of pasword encryption to use.
* Defaults to md5-hex.
* @param string $seed The seed to get the salt from (probably a
* previously generated password). Defaults to
* generating a new seed.
* @param string $plaintext The plaintext password that we're generating
* a salt for. Defaults to none.
*
* @return string The generated or extracted salt.
*/
function getSalt($encryption = 'md5-hex', $seed = '', $plaintext = '')
{
// Encrypt the password.
switch ($encryption)
{
case 'crypt' :
case 'crypt-des' :
if ($seed) {
return substr(preg_replace('|^{crypt}|i', '', $seed), 0, 2);
} else {
return substr(md5(mt_rand()), 0, 2);
}
break;

case 'crypt-md5' :
if ($seed) {
return substr(preg_replace('|^{crypt}|i', '', $seed), 0, 12);
} else {
return '$1$'.substr(md5(mt_rand()), 0, 8).'$';
}
break;

case 'crypt-blowfish' :
if ($seed) {
return substr(preg_replace('|^{crypt}|i', '', $seed), 0, 16);
} else {
return '$2$'.substr(md5(mt_rand()), 0, 12).'$';
}
break;

case 'ssha' :
if ($seed) {
return substr(preg_replace('|^{SSHA}|', '', $seed), -20);
} else {
return mhash_keygen_s2k(MHASH_SHA1, $plaintext, substr(pack('h*', md5(mt_rand())), 0, 8), 4);
}
break;

case 'smd5' :
if ($seed) {
return substr(preg_replace('|^{SMD5}|', '', $seed), -16);
} else {
return mhash_keygen_s2k(MHASH_MD5, $plaintext, substr(pack('h*', md5(mt_rand())), 0, 8), 4);
}
break;

case 'aprmd5' :
/* 64 characters that are valid for APRMD5 passwords. */
$APRMD5 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';

if ($seed) {
return substr(preg_replace('/^\$apr1\$(.{8}).*/', '\\1', $seed), 0, 8);
} else {
$salt = '';
for ($i = 0; $i < 8; $i ++) {
$salt .= $APRMD5 {
rand(0, 63)
};
}
return $salt;
}
break;

default :
$salt = '';
if ($seed) {
$salt = $seed;
}
return $salt;
break;
}
}

/**
* Generate a random password
*
* @static
* @param int $length Length of the password to generate
* @return string Random Password
* @since 1.5
*/
function genRandomPassword($length = 8)
{
$salt = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
$len = strlen($salt);
$makepass = '';

$stat = @stat(__FILE__);
if(empty($stat) || !is_array($stat)) $stat = array(php_uname());

mt_srand(crc32(microtime() . implode('|', $stat)));

for ($i = 0; $i < $length; $i ++) {
$makepass .= $salt[mt_rand(0, $len -1)];
}

return $makepass;
}

/**
* Converts to allowed 64 characters for APRMD5 passwords.
*
* @access private
* @param string $value
* @param integer $count
* @return string $value converted to the 64 MD5 characters.
* @since 1.5
*/
function _toAPRMD5($value, $count)
{
/* 64 characters that are valid for APRMD5 passwords. */
$APRMD5 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';

$aprmd5 = '';
$count = abs($count);
while (-- $count) {
$aprmd5 .= $APRMD5[$value & 0x3f];
$value >>= 6;
}
return $aprmd5;
}

/**
* Converts hexadecimal string to binary data.
*
* @access private
* @param string $hex Hex data.
* @return string Binary data.
* @since 1.5
*/
function _bin($hex)
{
$bin = '';
$length = strlen($hex);
for ($i = 0; $i < $length; $i += 2) {
$tmp = sscanf(substr($hex, $i, 2), '%x');
$bin .= chr(array_shift($tmp));
}
return $bin;
}
}
?>